The disclosure relates to a valve block arrangement having a closed center valve block which has at least one main spool, in order for a hydraulic consumer to be controlled by means thereof. The disclosure also relates to a method for controlling the valve block arrangement.
Closed center systems involve a hydraulic circuit in which directional valves for controlling consumers are closed when in their central position. The volume flow is then, in the case of closed directional valves, conducted normally via a recirculation valve in the case of fixed displacement pumps being used as a pressure medium source. In the case of an open center system, a hydraulic circuit is provided in which series-connected directional valves for controlling consumers are open to the oil flow when in their central position, such that a pump delivery flow of a fixed displacement pump can be conducted through all of the directional valves. If only one directional valve is provided, then in the central position thereof, the pressure medium volume flow can be conducted to the tank, thus being referred to as neutral recirculation.
DE 10 2012 218 428 A1 discloses an open center valve block. Said valve block has a multiplicity of main spools for controlling consumers. A respective main spool can be fed in parallel with pressurized fluid via a first and second pump channel. The fluid flow flowing from each of the pump channels is controlled by means of an associated first and second auxiliary spool respectively.